Bow-drill



(No Model.)

, A. PRANKE.

BOW DRILL.

Patented Apr. 3, 18.88.

I In r8420). filtjllfll 2 2122250.

UNITED STATES PATnN'r rains.

AUGUST PRANKE, OF DETROIT, MICHIGAN.

BEOW-DRILL.

$PECIPICA'I'ION forming part of Letters Patent No. 380,517, dated April 3, 1888.

Application filed February 9. 1888. Serial No. 263,519. (No model.)

To all whom it may concern.-

Be it known that I, AUGUST PRANKE, a citizen of the United States, residing at Detroit, in the county of \Vayne and State of Michigan, haveinvented certain new and useful Improvements in Bow-Drills, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to new and useful improveznentsin that class of drills usually known as bow-drills; and the invention consists in the peculiar construction and operation of the parts, as more fully hereinafter described.

In the drawings which accompany this specification, Figure l is a vertical longitudinal section, and Fig. 2 is a cross-section on line x m.

A is the revolving center or drill stock, provided with the usual socket to removably se cure a drill or other tool therein.

B is a. handle provided with a central bore to receive the tail end of the drill-stock and form a bearing therefor.

G is a head or casing secured to the handle and provided with a bearing, a, for the drillstock.

D is a ratchet-wheel secured upon the drillstock in any suitable manner, preferably by securing it upon. a squared portion thereof.

E is a transverse aperture through the easing 0, and F is a set-screw holding the drillstock removably in position.

G is a rack or, rather, ratchet bar suitably toothed to gear with the ratchet-wheel D, and of a cross-section to freely pass through the transverse aperture E when engaging with the teeth of the ratchet.

H is a handle secured to one end of the ratchetbar.

In practice it will be seen that by means of a device described and constructed as shown a drill secured to the drill-stock may be operated in the same manner as with the ordinary bow-drill, while at the same time the device needs less care and attention in operating than the catgut bow,which is liable to run off the pulley or slip,which in my construction is not possible. Further, my device is very compact and can be constructed cheaply, and is especially designed and adapted for heavier work, such as drilling in stone.

Instead of making the case 0 separately of metal, as shown, it may be formed as an integral part of the handle.

\Vhat I claim as my invention is-- 1. In a drill, the eo1nbination,with the hen die or frame,of the drill-stock journaled therein, the ratchet-wheel secured upon the drillstock, and the rack-bar working through a transverse slot in the frame and adapted to engage with the ratchet, substantially as described.

2. In a drill, the combination, with the handie and drillstockjournaled therein,of the ease secured to the handle, the ratchet secured upon the d rill-stock, the transverse aperture through the case, and the ratchet-bar, the parts being constructed and arranged to operate substantially as described.

In testimony whereof I affix my signature, in presence of two witnesses, this 30th day of January. 1888.

AUGUST PRANKE.

\Vitnesses:

P. M. HULBERT, J OHN SOHUMAN. 

